Musculoskeletal Diseases and Disorders Chapter 15

Musculoskeletal System Bones Long, short, flat, irregular Compact, spongy Joints Bursae Muscles Tendons Ligaments

Musculoskeletal System Two divisions: Axial skeleton Appendicular skeleton (inc. pelvic girdle) Muscle types: Skeletal muscle (voluntary, striated) Smooth muscle (involuntary, non-striated) Cardiac muscle (involuntary, striated)

Disorders of Bone Spinal deformities Herniated intervertebral discs Osteoporosis Osteomyelitis Paget’s Disease (osteitis deformans) Fractures

Spinal Deformities Lordosis Abnormal “inward” or anterior curvature Accentuation of normal curve of lumbar spine Frequently gradual onset Affects lumbar spine Also called “swayback”

Spinal Deformities Kyphosis Abnormal “outward” curvature of the spine Accentuation of normal thoracic spine curvature Also called “humpback” or “roundback” Commonly due to pathological fractures of spine in osteoporosis

Spinal Deformities Scoliosis Lateral (sideways) curvature of the spine May go to left or right May involve some rotation of spinal column May be caused by discrepancy in leg lengths Surgery possible if interferes with breathing or mobility

Spinal Deformities Etiologies Posture, leg length differences, congenital, epiphyseal growth disturbance, trauma, tumors, infection, arthritis, TB, endocrine abn, aging S/S: usually backache, fatigue, abnormal appearance or fitting of clothes Treatment: PT, exercise, braces, surgery, pain relief

Herniated Intervertebral Discs Disc Anatomy Annulus fibrosis Nucleus pulposis Herniation Nucleus pulposis pushes through annulus into spinal canal Rupture Pieces of the disc are free in the spinal canal

Herniated Disc S/S: Treatment: Back pain Paresthesias Sciatica: inflammation of sciatic nerve, leg pain Treatment: PT, exercise, pain relief meds, surgery (rarely), life correctly

Osteoporosis Metabolic disorder of bones Less bone mineral (calcium) than normal Over 10 million in US affected Post-menopausal females most commonly Bones are brittle, porous, easily broken More prone to pathological fracture

Osteoporosis Etiology: S/S: often asymptomatic until pathological fx. Genetics, calcium intake & dietary, sedentary lifestyle, estrogen, vit D, or adrenal deficiency, steroid use, alcoholism, etc S/S: often asymptomatic until pathological fx. Treatment: calcium supplements, meds (antiresorptive, restorative of lost bone, etc)

Osteomyelitis Acute or chronic bone infection Inflammation, edema, circulatory problems More common in children Etiology: Trauma most commonly with bacterial invasion from the skin Infection may also spread from adjacent tissues or blood supply

Osteomyelitis Risk factors: S/S: may be asymptomatic for years Diabetes, orthopedic hardware, splenectomy & SSA, hemodialysis, IV drug users S/S: may be asymptomatic for years Treatment: Long-term antibiotics, sometimes surgical debridement

Paget’s Disease Osteitis Deformans Chronic metabolic bone disease High rate of bone turnover (reabsorption & deposition) Thicker but softer bone is the result Patients typically over 40 YOA One or many bones Usually lower torse involve

Paget’s Disease Etiology: Unknown S/S: graduation onset of swelling & pain Treatment: PT, pain management, surgery Medications (biphosphonates or calcitonin) Joint replacements

Fractures Closed/simple Open/compound Greenstick Displaced Comminuted Segmental Spiral Pathological

Fractures Etiology: trauma or disease S/S: usually pain and swelling Treatment: Rest, decreased use Splint, sling, cast Surgery (ORIF, etc)

Joint Diseases Osteoarthritis Rheumatoid Arthritis Gout (gouty arthritis)

Osteoarthritis Most common form of arthritis Chronic inflammation causing degeneration and new bone formation Weight-bearing joints most common Knees, hips Common in older patients (over 55 YOA) In over 70 YOA, females more frequently affected

Osteoarthritis Etiology: S/S: Treatment: Mechanical, chemical, genetic, autoimmune, metabolic Aging seems to be important S/S: May be asymptomatic indefinitely Pain, swelling, sometimes erythema, limitation of motion Treatment: Anti-inflammatories, PT, exercise, surgical

Rheumatoid Arthritis Chronic, systemic, polyarticular inflammatioy disease Destruction (erosion) of bone & cartilage Causes ankylosis (fibrous fusion of joints, immobile) Exacerbations and remissions unpredictable Affects mostly females Increasing risk with advancing age

Rheumatoid Arthritis (RA) Etiology: autoimmune, genetics S/S: symmetric pain, swelling of hands & fingers, also other LE joints, systemic (fever, fatigue, wt. Loss) Dx testing: Rheumatoid factor blood test Treatment: Antiinflammatories, PT, antimetabolites, antirheumatic drugs

Gout Gouty arthritis Chronic uric acid metabolism disorder Uric acid crystals deposited in joints Tophi formation (urate compounds) around joints Acute, severe episodes of arthritis Mostly male patients Other associated problems: Kidney stones, renal failure, hyperuricemia

Gout Etiology: S/S: Treatment: Metabolic, renal, some genetics Severe signs & symptoms of inflammation Big toe is classical site Treatment: Pain relief, antiinflammatories, colchicine, diet low in purines, alopurinol

Muscles & Connective Tissue Diseases Sprains & strains Bursitis & tendonitis Carpal Tunnel Syndrome Myasthenia Gravis (MG) Polymyositis Systemic Lupus Erythematosus (SLE) Duchenne’s Muscular Dystrophy

Sprains & Strains Sprain Strain Etiology: trauma or overuse Ligamentous tearing/stretching after a tortion injury Strain Tearing/stretching of tendon or muscle Etiology: trauma or overuse S/S: localized pain, swelling, limitation of motion Treatment: supportive, pain relief

Bursitis & Tendonitis Bursitis Tendonitis Inflammation of fluid-filled bursae near joints Shoulder, hip, elbow, knee Tendonitis Inflammation of tendon or tendon-muscle attachement Shoulder, wrist, Achilles, hamstring Etiology: trauma, excessive use, other diseases S/S: pain, swelling, LOM, fluid accumulation

Bursitis & Tendonitis Treatment Varies with anatomic location & degree of disability Anti-inflammatories & pain relievers, splinting, exercise, orthotics, steroid injections, PT

Carpal Tunnel Syndrome Compression of median nerve within the carpal tunnel of the wrist Common syndrome with repetitive use work Involves pain, sensory & motor symptoms Etiology: edema within the carpal tunnel, causing inflammation of the nerve & other structures there

Carpal Tunnel Syndrome S/S: Wrist pain, burning or tingling paresthesias, numbness Weakness of hand grasp Tinel’s sign Treatment: Wrist immobilization, anti-inflammatories Rarely surgery

Myasthenia Gravis Rare, autoimmune disorder of the neuromuscular junction Antibodies against the acetylcholine receptors (post-synaptic) Chronic, progressive disease causing sporadic weakness of the skeletal muscles Most common in females, ages 20-40 YOA

Myasthenia Gravis (MG) Reduced muscle strength & longer recovery time with repeated use Symptoms late in the day Bulbar (eye & facial) muscles involved first Facial expression, drooping lids, etc. Thymomas in 15% MG patients 75% have some thymic abnormality (hyperplasia)

MG Diagnostic testing: Treatment: Tensilon test (edrophonium challenge will increase muscle strength) Treatment: Oral anticholinergic meds (pyridostigmine, neostigmine), immune suppressives, cholinesterase inhibitors like edrophonium Prognosis: normal life expectancy in modern times

Polymyositis Chronic, idiopathic inflammatory disease of connective tissues and muscles Exacerbations & remissions May have skin involvement (dermatomyositis) females more than males Bimodal peak of onset: 5-15 YOA & 50-70YOA

Polymyositis S/S: sudden or slow weakness of muscle group over weeks to months Often have trouble arising from sitting or raising arms above head, also voice changes Fever, fatigue, weight loss Skin: lilac-colored rash of eyelids, nose and face Dx via EMG & muscle biopsy Treatment: immune suppressive

Systemic Lupus Erythematosus Lupus or SLE Multisystem, autoimmune, inflammatory disease due to antibodies against cell nuclei Females outnumber male patients ( 9 to 1) Genetics may also be involved Arthralgias are first complaint in most patients

SLE Organ involvement: Four criteria at any time: Skin, renal, CNS, GI, blood, musculoskeletal, CV, pulmonary, vascular endothelium (Raynaud’s) Four criteria at any time: Malar rash or discoid rash, photosensitivity, arthritis, renal disease, neuro, skin, hematologic, or immune disorders, +ANA blood test

SLE Treatment: Anti-inflammatories, pain relief, immune suppressives

Duchenne’s Muscular Dystrophy Inherited, x-linked, recessive disorder Seen only in males Occasionally no family history Rapidly progressive wasting of skeletal muscles First in lower extremity & pelvis, then generalizes Usually appears by 6 YOA Cause of death: respiratory insufficiency usually by 25 YOA

Duchenne’s Muscular Dystrophy At first muscles appear larger Due to fat and CT infiltration Then atrophy (wasting, decrease in size) Then scarring & contractures Cardiomyopathy present in almost all cases

Neoplasms Osteogenic sarcoma Chondrosarcoma Malignant giant-cell tumor

Osteogenic Sarcoma Most common bone cancer 3rd most common cancer in adolescence Slightly more males Risk factors: radiation therapy, genetics Treatment: surgical, but mets later in 80% Most in long bones Femur, tibia, humerus (in that order)

Chondrosarcoma 2nd most frequent primary bone cancer (25%) Malignant tumor of cartilage Mostly over 40 YOA (mostly geriatric) Affects pelvis, femur, humerus, ribs

Giant Cell Tumor Multinucleated cells 5-10% of all giant cell tumors are malignant Recurs locally about 50% of the time Only 4-5% of all bone tumors Mostly long bones Mostly 20-40YOA Relatively good Px after tumor excision